Spaghetti with Lemon, Chile and Creamy Spinach

In a large saucepan of boiling salted water, cook the spaghetti until al dente. Drain and return to the saucepan.

Meanwhile, in a bowl, whisk the yogurt with the flour until smooth. In a large skillet, heat the olive oil. Add the garlic and chile and cook over moderately low heat, stirring occasionally, until fragrant, about 2 minutes. Add the yogurt and bring to a simmer over moderate heat, stirring. Add the spinach by the handful and cook until wilted, stirring. When all of the spinach has been added, stir in the lemon zest and juice and season with salt and pepper.

Add the sauce to the spaghetti and toss well to coat. Mound in bowls, sprinkle with the Parmesan and serve right away.